Finally got it figured out. The older, 9,000 Btu 'test' unit was not enough to cool down on a humid, mid 90's day. I found a new 12,000 Btu unit at Pep Boys for $479. They have a 9,000 Btu unit for $379. I know, alot more than those cheap, 5,000 Btu window units, BUT - no holes, no screws...